1. Field of the Invention
This invention relates to a pipe support system. More specifically, it concerns a system that provides vertical support for a horizontal pipe and that can provide secondary containment for leakage from the pipe.
2. Description of the Prior Art
When a small bore pipe is supported as a horizontal beam, the maximum spacing between vertical supports is often limited by considerations of excessive deflection, bending and shear stresses. The strength of pipe materials, such a plastics, further limit the support span, and for some plastic pipe compositions, a continuous support is necessary. In elevated temperature conditions, the strength and rigidity of the pipe can be seriously reduced. Small bore copper tubing requires a relatively short spacing between vertical supports.
In some installations of overhead pipe, secondary containment is required for the protection of personnel and/or equipment located beneath the pipe. A light weight sheet metal trough of semi-circular cross-section has been used to collect fluid and prevent dripping. These troughs lack the rigidity for supporting the pipe at maximum spacing between vertical supports.
V-shaped troughs have been used to provide support fo small bore pipe, but since these troughs are limited in depth, they do not have the section modulus needed for maximizing the support span. These troughs require a V-shaped hanger to interfit with the bottom of the trough. The hangers are expensive since they are made specifically for the troughs.
In a pipe support system, it is desirable to maximize the support span in order to reduce costs and to provide flexibility in design. The cost of a support includes not only the hanger or cradle hardware, but its installation in a structure. For example, it may be necessary to set threaded sleeves for receiving hanger rods in the framework for an overhead concrete slab before the concrete is poured. Cradles may require a support rack. These installation costs substantially increase the support cost. In an installation that requires numerous supports, by increasing the allowable support span, the total number of supports required can be reduced. Furthermore, it may be impossible to locate a support at a desired spacing because of an obstruction. In such a case, a support would be located on one side of the obstruction and if the support span was sufficient, the obstruction could be bridge. However, some pipe requires support every three feet and that may not be sufficient to bridge an obstruction.